Method of and means for fee sheets



Feb. 12, 1935. B, D. STEVENS 1,991,003

METHOD OF AND MEANS FOR FEEDING SHEETS Filed Feb, 6, 1951 2 Sheets-Sheet1 w1. 72061??? fluff 17 5:60am,

MW w Feb. 12, 1935. B, D. STEVENS I METHOD OF AND MEANS FOR FEEDINGSHEETS Filed Feb. 6, 1931 E 2 Sheets-Sheet 2 Patented Feb. 12, 1935UNITED STATES JHETHOD OF AND MEANS FOR FEIL SHEETS Burt 1). Stevens,Evanston, 111., assignor to The Miehle Printing Press & Mfg. Company,Chicago, 111., a corporation of Illinois Application February 6, 1931,Serial No. 513,805

33 Claims.

This invention relates to a method of and mechanism for feeding andconveying sheet material to operating machines such as printing pressesor the like where accurate register of the sheets is essential.

The invention specifically concerns sheet retarding means which willfunction to decelerate a traveling sheet before it is brought toregister.

While the principle of my invention may be applied to any type of sheetfeeding mechanism, it is particularly well adapted for use in connectionwith that class of sheet feeding apparatus in which is incorporatedsheet accelerating and transfer mechanism.

In such mechanism, when it is applied to a printing press for example,the sheets to be printed are engaged after having been brought toregister and while at rest on a sheet support and are subsequentlyaccelerated to the speed of a moving printing member, such as animpression cylinder, and transferred thereto so that at the time when asheet is grasped by the sheet holding means of the printing member, thesheet will have attained the surface speed of said member.

In automatically operated sheet handling machinery a stack or pile ofthe material to be fed is preferably placed on a supporting table wherethe sheets are separated, and thereupon conveyed individually toregistering means where each sheet is properly positioned prior to itsbeing transferred to a sheet receiving member, such as an impressioncylinder of a printing press.

The speed at which the separated sheets are advanced towards theregistering means is usually comparatively high because machines, suchas sheet fed printing presses, frequently handle sheets at a rate of3000 and upwards per hour.

It will be understood that when a sheet contacts with registering guidesat such a rate of speed, the sheet may rebound from the guides, or thoseportions of the leading edge which touch the guides may become indentedand thereby impair accurate positioning of the sheet. Therefore with aview to eliminating such conditions and in order to avoid contact of asheet against the registering guides at a high rate of speed, I haveprovided means whereby the sheets are slowed down before they reach theregistering means so that at the instant when the leading edge of asheet moves into contact with the front guides it will have nearly cometo rest, in other words the velocity of the sheet at that point willhave reached its Consequently a sheet will move very gently against thefront guides and any rebounding of the sheet, or indenting of itsleading edge will be avoided.

The primary object of my invention therefore is to provide mechanismwhereby sheets fed to registering means shall be effectively slowed down5 and brought to rest for registering purpose.

Another object is to impart such motion to the slowing downi. .e.retarding means that at the time when the leading edge of a sheetovertakes said means, the velocity of the latter will be approximatelythe same as that of the sheet.

A further object of my invention is the provision of means which shalleliminate any unevenness in the leading edge of a sheet to be fed, sothat said edge will be presented to the sheet registering means in aperfectly flat and straightened out condition. I

With a view to accomplishing these and other objects, I have conceived amechanism which is exceedingly simple in construction and. whereby anumber of auxiliary devices which heretofore have been essential, shallbe eliminated.

According to my invention, I provide means adapted to be operativelyassociated with the l sheet feeding, i. e. accelerating and transfer 25mechanism, which means preferably travels in a curvilinear path and isgiven a decelerating motion which I utilize to slow down a sheet priorto its reaching the registering guides.

Preferably the arrangement is such that at the moment when a sheetengages the retarding means, i. e. when a sheet is placed under controlthereof, the speed at which said means travels is merely a fraction lessthan the speed at which the sheet is fed. In this manner the sheet willnot be jarred when it overtakes said means, and therefore during thesubsequent slowing down, it will be under perfect control since itsleading edge will remain in proper alignment and will finally reach theregistering guides at an exceedingly slow rate of speed, in fact thevelocity of the sheet will be practically nil at the time when itsleading edge engages said guides.

The means whereby I accomplish the straightening or flattening out of asheet is preferably associated with the sheet retarding means in amanner that during the slowing down of a sheet the leading edge thereofis prevented from curling, while immediately'before the sheet is broughtto register any unevenness or wave in its leading edge shall beeliminated by means which will straighten out and hold the edge flatuntil the sheet is taken by the means whereby itis transferred to aprinting member or the like after the sheet has asumed its properregistering position.

I find that the preferred rate of decelera tion to be imparted to theretarding element is constant, that is, the angular velocity of saidsoclated sheet feeding embodying my invention;

FigureZisanenlargeddetail viewofthe sheet accelerating and transfermechanism shown in a podtion immediately after a sheethasbeenengagedbytheretardingmeans;

Figure3isasimilarviewbutshowingthe position of the sheet acceleratingand transfer mechanism andofthe sheet retardingmeansat the time when thesheet is in contact with its registering means and 'after it has beenengaged by the sheet holding elements;

Figure 4 shows the relative position of the transfer means and sheetholding elements of a printing member immediately after a sheet has beentransferred to the latter;

Flgure5isanenlargedsectionalviewshowing one preferred form andarrangement of the slowdown means in front elevation; and

Figure 6 illustrates one form of operating mechanism whereby motion istransmitted to the sheet transfer means.

In Figure 1 of the drawings, I have illustrated diagrammatically oneembodiment of my invention as applied to a rotary press, which includesa sheet transfer mechanism of the type referred to above and whereby'asheet to i be printed is transferred from the sheet feeding andregistering means at an accelerating speed to the impresion cylinder ofthe press.

The sheets .10 stacked on the feed board 11 are separated one by onefrom the pile and removed in succession therefrom by means of separators12, which may be of any well-known design, and whereby the separatedsheets are conveyed between a drop roller 13 and forwardingtapes 14 inorder to advance the sheet towards registering guides 15 providedadjacent thefront edge of the registering table 16. At that point, aftera sheet has been properly registered, it will be engaged by the sheetholding elements on the transfer gripper mechanism 17 while the sheet isat rest and then removed from the registering table 16 at anaccelerating speed, so that when the grippers 18 ofthe impressioncylinder 19 take over the sheet from the transfer mechanism 17, it willhave assumed the surface speed of the cylinder 19. The transfermechanism, after it has released a sheet, will continue to rotate andsubsequently its speed will be retarded so that the mechanism will cometo a stand still when it has again reached its sheet engaging position.

The sheet 10, while being. carried around by the cylinder 19, willreceive its impression as it passes between said cylinder and the formor 1,oo1,oos v plate on the cylinder 20, which plate will be inked inany well-known manner by inking mechanism such as indicated at 21.

Theprintedsheetisthentransferredfromthe cylinder grippers 18 to thedelivery grippers 22 mounted on endless around a delivery reel 24 andsprocket wheels 25 to bring a sheet into position over a delivery board26 onto which the printed sheets are deposited.

InFigures2and3Ihaveshownthesheet transfer mechanism and associated partson an enlarged scale in order to clearly illustrate their function forslowing down and registering a sheet prior to its being transferred to aprinting member or the like. The sheet accelerating and transfermechanism 17 includes sheet enga ing rippers 27 which are pivotallymounted at 28, and may be operated in any wellknown manner to open andclose. Preferably the arm 29 of the transfer mechanism is provided atits outer end with a shoulder 30, which serves as a means forstraightening out the leading edge of a fed sheet as will be hereinafterdescribed, and which in this particular form of arrangement also acts asa support or pad for the grippers 2'1. 'lhe arm 29 furthermore isprovided with a projection or projections 31 which extend into the pathof a fed sheet and which will operate to slow down a. sheet forregistering purpose as will be explained later. Obviously any desirednumber of grippers 27 and cooperating parts may be arranged on thetransfer mechanism, depending on the width of the sheets to be handled.

Inorder to provide clearance for the grippers 27 and projections 31, thefront edge of the registering table 16 is recessed so that a pluralityof tongues 32 will be formed which will timetion to support the leadingportion of a sheet across its entire width.

The front registering guides are molmted to swing about the axis 33 inorder to move into and out of their position as is well known in theart.

As indicated above, the sheet accelerating and transfer mechanism 17,which is mounted to rotate about the axis 34, transfers a registeredsheet from the table 16 to the grippers 18 at an accelerating speed, inother words, the sheet will be engaged by the grippers 27 while at restand advanced at an increased velocitysothatwhenthesheetispresentedtothegrippers 18, it will have reached thesurface or Imiform speed of the cylinder 19. Thereupon the transfermechanism continues to rotate until it reaches a point at which theslowdown fingers 31 are located in a position approximately as indicatedin broken lines in Figure 2 where the deceleration of the transfermechanism commences.

While on the accompanying drawings I ,have shown the slow down fingers31 as being integral with the transfer gripper mechanism, it will bereadily understood, however, that said fingers could be convenientlyarranged and operated independently of the transfer grippers. The methodof transferring sheets as illustrated is in itself not novel in the artand therefore does not immediately concern my invention, which, asstated above, has for its primary object the control and slowing down ofa sheet for registering purpose. Furthermore. it would be practical toapply the' principle of my invention in connection with other types ofsheet transferring means, such as chains23.whichpass.

oscillating stop gripper mechanism, according to which the transfergrippers, instead of performing. a complete revolution, merely oscillatebetween the sheet registering means and the impression cylinder or thelike for the purpose of transferring a sheet to the latter at anaccelerating. speed. The arrangement could also be such that aregistered sheet can be taken over direct by the grippers of animpression cylinder or the like, a method which is well known in the artof sheet handling equipment.

Therefore I need not deal at length with the tion to the edge of a fedsheet, will have a tendency to divertfrom its path of travel and curlupwardly. v This tendency, however. is effectively overcome according tomy invention by imparting to said fingers during their slowing down motion a relative movement to the fed sheet so that the leading edge ofthe sheet will remain in its proper plane. In the arrangement shown. inwhich the fingers 31 are mounted above the registering table 16 andtravel in a curved path, said relative movement will be in a downwarddirection. Therefore, due to the engagement of a fed sheet with the face35, the leading edge of the sheet will be urged downwardly andconsequently will remain flat on the table 16, so that it will The speedof the slow down fingers 31, at the moment whena sheet overtakes them,is approximately that at which the sheet travels, necessarily somewhatless. The retardation of the sheet is gradual and'preferably parabolic,as explained above, that is to say, the curve representing the angularspeed of the slow down means during the retardation of a sheet is thatof a parabola. I

The front registering guides 15 are about to swing upwards into theiroperative 'or register-v ing position when the slow down fingers 31 havereached a locationapproximately as shown in Figure 2, so that a sheetwill be brought to bear against said guides just before it comes torest. Due to the extremely low velocity of a sheet at the time when itreaches the registering guides, any rebounding of the sheet from theguides is eliminated and consequently the registering position of thesheet'will not be disturbed.

In order that the leading edge of a sheet to be registered will be freeto align itself perfectly with its registering means, the slow downfingers 31 will pass slightly beyond the stops 15, as is clearlyindicated in Figure 3.

The relative position of the cooperating parts as shown in Figure 3 isthat at which a sheet has been registered and immediately after thegrippers 27 have closed on the sheet for the purpose of transferring itto the cylinder 19. Prior to the commencement of the transfer motion ofthe grippers 27, the registering guides will move out of their operativeposition into a position shown in Figure 4 to clear the path for thesheet. In Figure 4 the sheet is shown in its position on the cylinder 19after the grippers 18 have engaged it and after the transfer grippers 27have opened and released the sheet. From that point on the transfermechanism. 17 will continue to rotate, preferably at a uniform speed,until the position indicated by broken lines in Figure 2 is againreached, where the deceleration will commence as explained above.

The function of the shoulders 30 for finally flattening out the leadingedge of a sheet, and which shoulders in the preferred form shown.alsoserve as supports or pads for the grippers 27, is illustrated inFigures 2 and 3. During the slowing down motion of the retardingelements orfingers 31, said shoulders will gradually approach the top ofa fed sheet until the position in Figure 3 is reached, when saidshoulders will be located in the plane of the sheet, see also Figure 5.

reached its registered position, i. e. the end of its deceleration, theleading edge of the sheet will be presented to the registering guides ina perfectly fiat condition due to the cooperation of the shoulders 30with the sheet supporting tongues 32. The driving means for imparting tothe sheet transfer mechanism its rotary, accelerating and deceleratingmotions may comprise any suitable mechanical movement, which in turn maybe of any desirable or known design. In Figure 6 I have illustratedmerely by way of example one form of mechanism whereby the actuation ofthe sheet transfer elements will be accomplished.

Gear sectors 36, 37 and 38 are rigidly mounted on the transfer grippershaft 34 to rotate "therewith. Said shaft also carries a bracket 39provided with cam rollers 40 and 41.

.The shaft 42 which is the driving shaft has rigidly mounted thereoncomplementary gear sectors 43, 44 and 45 as well as a cam member 46.These gear sectors together with the cam 46 rotate as a unit in thedirection indicated by the arrow. It will be seen that in the positionshown in Figure 6, the rollers 40 and 41 ride over the cam 46 at whichtime theshaft 34 and consequently the sheet accelerating and transfergripper mechanism will be' at rest. Upon continued. rotation of theshaft 42, the extension 47 of the cam 46 and over which the roller 41rides, will cause the shaft 34 and gear sectors thereon to rotate in ananti-clockwise direction and the gearsector 43 carried by the shaft 42will subsequently move into meshing relation with the complimentary gearsector 36 carried by the shaft 34. While these two sectors are in mesh,the shaft 34 and therewith the transfer mechanism will be given I anaccelerating motion until the sector 44 meshes ferred. The uniform speedis maintained so long as the sectors 37 and 44 remain in mesh and untilthe elliptical gear sectors 38 and 45 move into meshing relation.

It has been found that under certain conditions, it is desirable to gainadditional time for the purpose of registering a sheet. This isaccomplished by the provision of elliptical gears such as sectors 38 and45 which, after the uniform speed has been reached for transferring asheet from the transfer mechanism to the printing member or the like,will produce additional acceleration of the transfer mechanism andconsequently time will be gained in order to permit of a longer dwell ofsaid mechanism for the purpose indicated above.

However, normally it will not be essential to produce any additionalacceleration so that the provision of elliptical gears is merelyoptional and will not become necessary in the majority of constructions.Therefore in order to continue the uniform motion, after a sheet hasbeen transferred, the gear sectors 37 and 44 may be extendedcorrespondingly, while complementary gear sectors will be arranged toproduce the deceleration of the transfer mechanism until the rollers 40and 41 again ride over the cam 46 during which period the transfermechanism will remain stationary for the purpose set forth.

As indicated above, various modifications could be embodied in thedesign as well as in the arrangement of my novel sheet controlling meanswithout departing from the principle of my invention; therefore, I wishit to be understood that I intend to cover any such constructions andapplications of my invention that will come within the scope of theappended'claims.

I claim:

1 In a printing press, rotary sheet transfer elements including sheetslow down means adapted to engage the leading edge of a moving sheet andto decelerate same before the sheet is brought to register at rest.

2. In a -printing press, rotary sheet transfer elements including sheetslow down means moving in a curvilinear path and adapted to engage theleading edge of a moving sheet and to decelerate same before the sheetis brought to register at rest.

3. In a printing press, rotary sheet transfer elements including sheetslow down means having accelerating and decelerating motion and adaptedto engage the leading edge of a moving sheet and to decelerate samebefore the sheet is brought to register at rest.

4. In combination, sheet registering front guides,

and sheet transfer elements traveling in a con-' tinuous path and,including sheet slow down means adapted to engage the .leading edge of amoving sheet and to bring it substantially to rest before the sheet ispresented to said front guides.

5. In combination, sheet registering front guides, and sheet transferelements traveling in a continuous curvilinear path and including sheetslow down means moving therewith and adapted to engage the leading edgeof a moving sheet and to bring it substantially to rest before the sheetis presented to said front guides.

6. In combination, sheet registering front guides, and sheet transferelements traveling in a continuous path and including sheet slow down.means having accelerating and decelerating motion and adapted to engagethe leading edge of a moving sheet and to bring it substantially to restbefore the sheet is presented guides.

7. In a sheet conveying apparatus, the combination of a sheet support, amember for performing an operation on a sheet, transfer gripper elementsto transfer a sheet from said support to said member, and sheet slowdown means carried by said transfer elements to slow down andsubstantially stop a sheet prior to its being registered and transferredto said member.

8. In sheet conveying apparatus, the combination of a sheet support, amember for performing an operation on a sheet, sheet transfer elementstraveling in a continuous path and adapted to transfer a sheet from saidsupport to said member, said transfer elements including a rotary sheetslow down means operative to slow down to said front and substantiallystop a sheet prior to its being transferred to said member.

9. In a sheet registering means, a sheet retarding element moving in acurvilinear path above the sheet and downwardly through the planethereof, said element being' adapted to engage a moving sheet to causepreliminary register and to slow it down before the sheet is brought tofinal register.

10. In a sheet registering means, a sheet retarding element moving in acurvilinear path above the sheet and downwardly through'the planethereof, said element being adapted to engage a sheet traveling in arectilinear path to cause preliminary register'and to slow it downbefore it is brought to final register.

11. In combination with sheet registering means, a sheet retardingelement moving in a curvilinear path and adapted to engage a sheettraveling in a rectilinear path to slow down and substantially stop itbefore it is brought to register, the angular position of said retardingelement with relation to the leading edge of the sheet being such thatsaid edge is biased downwardly by said element, during its slowing downmotion.

12. In combination with sheet registering means, a sheet retardingelement moving in a curvilinear path and adapted to engage a sheettraveling in a rectilinear path to slow it down before it is brought toregister, said retarding element having such relative movement to theplane in which the sheet travels so as to avoid diverting of the leadingedge of a sheet from its path.

13. In sheet transfer mechanism including sheet engaging elements havingaccelerating and decelerating motion, registering means, and aretardingelement traveling in a curvilinear path at a decelerating speedand adapted to slow down and substantially stop a moving sheet before itis brought to register.

moving sheet before it is brought to register, one' of said engagingelements acting to flatten out the leading edge of a sheet before it isregistered' 15. Sheet feeding means, comprising in combination mechanismincluding intermittently moving sheet carrying elements to engage asheet while at rest and to transfer it to a sheet receiving member,means to convey sheets towards said mechanism, the carrying elementshaving accelerating anddecelerating motion arranged to cause a sheet tobe slowed down by the deceleration.

16. Sheet feeding means, comprising in combination mechanism includingintermittently moving sheet carrying elements to engage a sheet while atrest to transfer it to a sheet receiving member, means to convey sheetstowards said mechanism, slow down fingers extending into the path ofsheets fed to said elements, and means cooperating with said fingers tostraighten and flatten out the leading edge of a sheet.

17. Sheet feeding means, comprising in combination mechanism includingintermittently moving sheet carrying elements to engage a sheet while atrest and to transfer it to a sheet receiving member, means to conveysheets towards said mechanism, and slow down fingers having acceleratingand decelerating motion, arranged to slow down a sheet and to avoidcurling up of the leading edge thereof prior to the sheet beingtransferred to said sheet receiving member.

18. In a printing press, sheet transfer elements including slow downmeans comprising a member for decelerating a fed sheet and having arelative movement with respect to the sheet when in engagement therewithto prevent curling of the leading edge of the sheet.

19. In a printing press, sheet controlling means comprising a memberarranged above the path of a sheet for decelerating a fed sheet andhaving a relative movement with respect thereto when in engagementtherewith to prevent curling of the leading edge of the sheet.

20. In a printing press, sheet transfer gripper mechanism includinggripper and cooperating pads and a member moving in a curvilinear pathfor decelerating a fed sheet and having a relative movement with respectthereto when in engagement therewith to prevent curling of the leadingedge of a sheet, said gripper pads being adapted to flatten out saidleading edge for registering purpose.

21. In sheet conveying apparatus, the combination of a sheet support, aprinting cylinder, and intermittently actuated transfer grippermechanism for transferring a sheet from said support to said cylinderand including sheet slow,

down means operative to slow down and stop a sheet prior to its beingregistered and transferred to said cylinder.

22. In sheet conveying apparatus, the combination of a sheet support, aprinting cylinder, intermittently actuated transfer gripper mechanismfor transferring a sheet from said support to said cylinder, and sheetslow down means coaxial with said transfer gripper mechanism andoperative to slow down and substantially stop a sheet prior to its beingregistered and transferred to said cylinder.

23. In sheet feeding mechanism, the combination of a sheet carrierwhereby a sheet will be grasped and carried to a moving printing member,and means associated as a. unit with said carrier to slow down and bringa moving sheet to substantial rest so that it may be brought to registerbefore it is grasped by said carrier.

24. In sheet feeding mechanism, the combination of a rotary sheetcarrier whereby a sheet will be grasped and carried to a moving printingmember, and means associated as a unit with said carrier to slow downand bring a moving sheet to substantial rest so that it may be broughtto register before it is grasped by said carrier.

25. In combination with sheet feeding means,

to slow down and stop a sheet for registering purpose.

26. In combination with sheet feeding means, sheet registering means, asheet retarding. element moving in a curvilinear path above and into andout of the sheet path to slow down and stop a sheet for registeringpurpose, said retarding element passing beyond said registering meansafter a sheet has reached its registering position.

27. In combination with sheet feeding means, sheet registering means, asheet retarding element moving in a curvilinear path above the plane inwhich the sheet travels to engage, slow down and stop a sheet forregistering purpose, said retarding element passing beyond saidregistering means after a sheet has reached its registering position.

28. In combination with sheet feeding mechanism, sheet registeringmeans, rotary sheet retarding means, supporting means extending acrossthe full width of a fed sheet to support the leading edge of the sheetwhile being registered, and means on said retarding means cooperatingwith said supporting means to flatten out a sheet for registeringpurpose.

29. In combination with sheet transfer mechanism including grippers andgripper pads, sheet registering means, sheet retarding means associatedwith said transfer mechanism, and sheet supporting means extendingacross the full width of a fed sheet to support the leading edge of thesheet while being registered, said gripper pads cooperating with saidsheet supporting means to flatten out a sheet for registering purpose.

30. In combination with sheet transfer mechanism, sheet engaginggrippers traveling in a curvilinear path, sheet retarding elementassociated with said grippers and rotating above the sheet and in thesame direction as said grippers to engage a sheet and slow it down forregistering purpose, the sheet engaging portions of said gripperstraveling in a plane below the path of the sheet during the slowing downof a sheet.

31. In intermittently operating sheet transfer mechanism havingaccelerating and decelerating motion, the combination of means wherebythe deceleration of said mechanism is utilized to slow down a sheet ofmaterial for registering purpose.

32. The method of feeding sheet material to printing presses or the likeconsisting in advancing separated sheets towards registering means,slowing down the sheets by deceleration and then stopping them,preventing curling of the leading edge of a sheet during the slowingdown of the sheet, registering the sheet, and transferring theregistered sheet at an accelerating speed to a printing member.

33. The method of feeding sheet material to printing presses or the likeconsisting in advancing separated sheets towards registering means,slowing down the sheets by deceleration and then stopping them,preventing curling of the leading edge of a sheet during the slowingdown or the sheet, flattening out the sheet along its entire front edge,registering the sheet, and transferring the registered sheet at anecgcelerating speed to a printing member. v

BURT D. STEVENS.

